Sunday 22 July 2012

Preparing to Breed Silk Moths


Now that is real eye-catcher of a blog title. Yuck.

Working in the villages in Laos I was shocked to see the mess of silkworm eggs laid haphazardly on cloth with dead moths stuck to the edges of a basket . The powder on the moth wings is said to be the source of most sicknesses in silkworms. It gets on the eggs and then the following batch of silkworms gets sick.

I've also seen friends in Japan show up with a bunch of silk moth eggs stuck to a cocoon. It sends shivers up my spine. It is so not hygienic. Here is some advice for would-be silk moth breeders.

Let's go back a few days...

First, get the silkworms that are making cocoons away from the silkworms that are still eating. The traditional silk farmhouses (like mine) were designed that there was an upstairs floor (often a half height floor) that the spinning silkworms were brought to be away from the late spinners. There was the practical purpose for this as well. The huge amount of leaf waste had to be disposed of, but the focus of several days work was to get the silkworms to a clean, warm place where they can make good quality cocoons.

If the weather is humid the waste can get moldy in a matter of hours. The silkworms get rid of excess liquid from their bodied only once. This high ammonia waste can kill other silkworms as well as create a generally bad condition for all worms. I've raised 20 000 worms at a time and the days they start to spin is a crucial time to keep things very clean and organized and prioritized.

A week or so later, it is more important to keep silk moths away from the area where silkworms will be raised. When breeding a lot of silkworms I have a morning shower wear fresh clothes. I wash my hands and arms and all equipment with a disinfectant.  A face mask doesn't hurt. I choose the best shaped cocoons. The ones with the finest patterns on their surface. After cutting open the cocoons I choose the best formed and colored chrysalis and separate the males and females. When the moths emerge I choose the best formed ones with no bent wings and discolored abdomens etc. (Fairly evil-eugenic-minded stuff here.)

These three were rejects this time.
One was made in a mulberry leaf so it has a flat side and therefore can't be judged properly. The middle guy was a shrimparoo. The third one had a poorly spun end. This one can't be reeled easily. There is a good chance that this moth's offspring would have the same kink in their spinning skills and make 500 cocoons with the same characteristic.
Thin ended cocoons like this were made by a silkworm who didn't like the contorted position necessary to spin the ends well. When boiled the air escapes through the end and the cocoon sinks and unravels unevenly. Not conducive to easy and even reeling. 

Here is a hint. Although the silkworms are out of their protective cocoons, when it comes time, they break out of the thin paper-like chrysalis cover and emerge as moths and then excrete a really horrible the-Joker-in-Batman-would-use-as-a-weapon-liquid to melt the cocoon (that isn't even there) so they can break out. This liquid is so strong it can eat away at the nearby chrysalis. So the trick is to make this paper folding thing to cut down on nasty alkali cocoon melting spray and get the moth above the mess as quickly as possible. Males and females separated I arrange the whole event like this for each: 








Looking at these pictures and considering the topic.... I must have some Buckminster Fuller/2001 Space Odyssey Silk Farming Fetish.

It just isn't so.

OK..... When the moths emerge in a few days, I will continue with the process description.  I wonder if anyone out there will actually use this information?

And on a lighter note...the radiation reading was below normal on Geiger's geiger counter! I hope Japan moves away from nuclear power but I doubt they will. Too much vested interest. The Japanese are not comfortable to confront authority and power directly.  I fear the backlash on those who are doing that now.






13 comments:

  1. The information that you provide, based on your amazing amount of experience and gathered knowledge, is invaluable.

    I don't comment much but I follow your every post. And once of these days I swear I'll get back to Japan and finally come and meet you!

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    1. Hi Alfred,
      When I start writing it down, I realize there are a million little important details and find it hard to know where the 'too much information' line is! Look forward to meeting you.
      Bryan

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  2. I don't know if I will ever use the information, but I love learning about the process. :)

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  3. onesmallstitch23 July 2012 at 13:05

    love the paper thingy - very clever! Nice to know Geiger is ok, he doesn't look very comfortable.

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  4. I will never raise silkworms, but these posts are so interesting. It is a completely and fascinating new world for me.
    You should collect your posts in a little booklet (like the one that the lady wrote on indigo and that you gave us).

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  5. Hi Blandina, I will one day. I will. I just can't get the exact angle from which I want to write. How much technique, how much history and how many personal stories. Thanks for the encouragement. Hope life is good for you in the Italian summer, your lovely city swamped with tourists.
    B

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  6. i'll never raise silk worms, but being a silkophile i find your posts fascinating. good to hear the counter's down. oh and the moth segregating architecture is very cool!

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  7. I don't think I will ever raise silkworms either, especially as I now know you have to be so ruthless and weed out the weak and the helpless, the disabled and the deformed. I love reading your posts though!
    So is Geiger still with you? Just asking!

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  8. i really like reading about raising silkworms. the hygiene issue is global, all farmstock benifit from good practices. i once raised and released a cecropia whose cocoon i found...and eventually i spun that golden brown cocoon!

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  9. Hello Bryan. Another reader who is not going to raise silk worms but who reads your blog regularly and is totally absorbed by the process you are describing. Don't stop - you have an audience! I hope that tsunami of an email I sent you did not put you off thinking about a paper based course? I will write again soon and see if there is still interest on your side - certainly is on mine, and those few to whom I have spoken.

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    1. Hi Susan,
      I have you already booked in my head and I go over the possibilities on a daily basis. I am away for a few days and will get back to you when I am back at home.
      Bryan

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  10. Like chefs say, carnivores should look into the eyes of the beast they will eat... I find it fascinating, if not a little sobering, to really understand just how much work goes into making up a spool of silk thread that I happily if not obliviously stitch with. So thank you for you very in depth writings and photos... They ARE really interesting. (they also make for great armchair travel stories... sigh... One day I'll get there!!)
    Cheers
    Samm (a newish follower, first time commenter!!)

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  11. Thank you everyone for the comments. I will expand on the process over time. All the small details I found mundane over the years now seem precious. It is wonderful to have you interested.
    Bryan

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